Plug-in for Netbeans for editing images, with background erase
This is a simple pixel editor which plugs into Netbeans. It has the useful "magic erase" feature, where you give it a background and foreground color, and the pixel will be made transparent if it is near the background color.
A pre-compiled version is available at https://jfaden.net/~jbf/netbeans/com-cottagesystems-imagetool.nbm .